Alternating-current rectifier.



E. PA'ssLER. ALTERNATING CURRENT RECTIFIER.

APPLICATION FILED NOV. 5, 1910.

1,131,920. Patented Mar. 16, 1915.

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W/TNE88E8: yn/70R 9C. 3 9? Ffssfler forming part of this specification.

teryand from its UNITED. STATES OFFICE.

ERNST FASSLER, OF FRANKFORT-ON-THE-MAIN, GERMANY, ASSIGNOR TO WAGNER ELECTRIC MANUFACTURING COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

' ALTERNATIN G-CURREN T RECTIFIER.

r rnnr Specification of Letters Patent. Patented Mar 16, 1915.

Application filed November 5, 1910. Serial No. 590,858.

To all whom, it may concern;

Be it known that I, ERNST Fi'issLEn, a subject of the Emperor of Germany, residing at Erankfort-on-the-Main, in the Emtromagnet 6 as soon with the contact 13.

as it comes into touch 0 pire of Germany, have invented a certain \vi 1 always be opposed to the alternatin E. new and useful Alternating-Current Recti- M. F. during one-half cycle and will always fier, of which the following is such a full,

be of the same direction as said alternatin 'E. M. F. during the other half cycle. The

clear, and exact description as will enable any one skilled in the art to which it apperalns to make and use the same, reference being had to the accompanying drawings,

y invention relates to taining from an of supply a current in which the impulses magnitude other direction thus giving a applications, equivalent to that produced by a uni-directional acting in the circuit 4, 8, 6, l1, l6, l7, 5, 2O fore impressed on the el net 6, when the contact 14 does circuit said electromagnet, is the attery and of the line E. M. F. and is itself w an alternating E. M. F. but with unequal The object of my invention is to produce Th impedance a simple, commercially practical device of this chhracter and one which is particularly adapted for charging storage batteries.

' he accompanying drawing is a diagramthe support 8 and the battery I and which comprises the electromagn is made high, or instance by winding the magnet with many turns of limiting the current through said magnet to 1 represents a suitable source of alternatth d sired eXtentmg current supply, such for instance as an e Spr111g'9 and the armature 1 0 atalternating current generator, connected to are so adjusted that their pcthe primary 19 of a transformer by way. of t e mains 2 and 3. The secondary 20 of said transformer feeds the rectifying circuit which contains a storage battery 16 and an electromagnet 6, the windings of which are adapted to be short-circuited by the movement of an armature 10. i

The connections can be traced as follows: from the terminal 4 of the transformer to he support 8, through conductor 7, the of th windings of the electromagnet 6 and the conductor 12 to the adjustable contact 13, thence to the terminal 11 of the storage batterminal 17, ductor 18 back to the terminal 5 of the secondary 20 of the transformer. A spring 9 electromagnet 6. is attached to the support 8, and carries the armature 10 of the electromagnet 6 and a contact lladapted to cooperate with the contact 13. The adjustable stop 15 serves to limit the travel of the spring 9 away from the magnet. Because the contact .14 is electrically connected to the su port 8 it W111 short-circuit the windmgs o the elecsame order of frequency of the alternating spring mounted armature and the alternations of the flux impulses sum of the natural direction as the electromotive force 0 through the magnet controlling the frequency of said armature depends on the sign and magnitude of the difference between the frequency of the spring mounted alternation armature and the frequency 0 of the controlling flux impulses or 0 the controlling alternating If the natural frequency of vibration of the spring mounted armature is less than the frequency of the alternating E. M. then the armature will vibrate synchronously with said of its vibration will lag behind the phase of the flux impulses, the lower natural frequency of the armature mechanically producing an e ect on the phase of the armature vibration similar to that produced by an impedance on the phase of the current in an electrical cir cuit. If the natural frequency of vibration of the spring mounted armature is the same as that of the alternating E. F. resonance will occur, the armature vibrating in synchronism and in phase with the flux impulses. If the natural frequency of vibration of the spring mounted armature is higher than that of the alternating E. M. F. then it will vibrate synchronously with the flux impulses but the phase of will lead the phase of said impulses, the higher natural frequency of the armature, effect on the vibration similar to base of the current in an electric circuit. The spring 9 should ,in addition be of suffi stiffness not to respond, when at rest, to the attraction of the magnet 6 at the time when the energizing current of the electromagnet is due to the difference between the alternating and the unidirectional E F.s. This spring, should however, respon even when at rest, when said ener izing current is due to the sum of said M. F.s. It is not necessary to inter ose a transformer between the source 0 the alternatin E. M. F. and the rectifying circuit, but it will usually be convenient-to do so.

. The operation of the device is asfollows:

a negative direction and opposes the electromotive force-of the battery 16, then the current in themagnet 6 will be due to the difference between the two E. M. F-.s and will not be of sulficient strength to draw the armature toward the magnet. The next M. F. wave wil be in the positive and therefore in the fsarple t e battery} 16 and the greater flow of current in the magnet 6 due .to the sum of the two E. M. Fs will be suflicient to attract the armature 10, thus initiating its vibration. it has already been pointed out that the time constantof thecircuit containing the electromagnet is so chosen and the armature its vibration 6 while of the spring electromagnet will be is so tuned that the phase of its vibration, when in full swing, lags substantially 180 degrees behind the alternating E. M. F. impressed on the magnet 6. For this reason the spring 9 will not begin to be attracted until the positive alternating E. M. F. begins to decline and will not short-circuit the magnet 6 in normal operation until the direction of the E. M. F.s from the transformer (or the alternator) has been reversed becoming negative and thus'of opposite direction to that of the battery. This short-circuiting of the magnet 6 during the alternating wave opposing the battery E.

M. F. reduces the impedance of the circuit during that time and allows a charging currentof sufficient amplitude to low from the transformer into the battery along the circuit constituted by the terminal 4, the support .8, the spring 9, the contacts 14: and 13, the terminal 11, the battery 16, the terminal 17 the conductor 18 and the terminal 5. The time interval during which the electromagnet is to' remain short-circuited can be adjusted by means of the movable contact 13. This adjustment should be such that the shortcircuit around the magnet 6 will be open during the succeeding or positive E Wave when the current, irrespcctively of its direction will again be reduced to the comparatively small value determined by the impedance of the magnet 6. This small current nevertheless magnetizes the electromagnet just as it did at the outset and eventhe impulse it requires in order to keep v1- brating. It will be evident,

the battery Y 16 receives the strength of the current alternating E. M. F. in a direction to charge it, it can only send out a very small discharging current with the result that it will become fully charged just as if it were subjected to a unidirectional E. M. F. or current of suitable direction and strength.

In the foregoing description of theoperation of this rectifier it has been assumed liq-hath the battery was so connected that its half cycle of the alternat'ng E. M. F. an it was shown that under these conditions the vibration of the spring mounted armature will be initiated during the positive half cycle and that said armature will shortcircuit the electromagnet d part of the negative half time when the alternating E. M. F. opposes the battery E. M. F If the connections of the battery to the terminals 11, 17 of the rectifier are reversed then the battery E. M. F. will oppose the positive half cycle of the alternating E. M. F., the vibration mounted the negative half cycle and the short-circuited during therefore, that full from the source of tiatcd during F. was in o osition tothe ne ative pp g 115 armature will be 1111- IQU W en the alternating E. opposes the when said armature isln ts attracted posi battery E. M. tion, sa1d-armaturehaving a' natural fre- It will therefore be evident that with my quency of vibration approximating the alterconstruction it is immaterial how the batnat 1n g electromotive force impressed on the tery 16 is connected to the terminals 11 and exciting. coil of the electromagnet, but suflislnce a reversal of the battery terminals ciently diiferenttherefrom that the phase of automatically displaces the time phase of the actual vibration of the armature resulte spring vibrations by 180 degrees, thus ing rom the influence of the exciting flux always causing the electromagnct to .be of t e magnet and the armatnres natural time when the alternating E. M. F. opposes. to t e phase ofthe alternating E. M. F. 5 t e battery E. M. F. and a source of unidirectional E. M. F. conaving fully described my invention, nected in series with the exciting coil and what I claim as new and desire to secure the source of alternating E; M. F by LettersPatent of the United States is: v 3. In an alternating current rectifier, the 1, In an alternating current rectifier, the combination with a source of alternating comlaination with a source of alternating E. M. F., of an electromagnet having an exciting coil in circuit with said source, an an armature actuated by said'electromagnet armature actuated by said electromagnet and adapted to establish a short circuit beand adapted to establish a short circuit be-- tween the terminals of the exciting coll 5 tween the terminals of the exciting coil when when said armature is in its attracted posi- VlblatlOn approximating the frequency of mating electromotive force impressed on the alternating electromotive force imsaid electromagnet, but sufficiently difpressed on the exciting coil of the electroferent therefrom that the phase of the magnet, but sufliciently different therefrom actual vibration of the armature resultthat the phase of the actual vibration of the ing from the influence of the exciting flux armature resulting from the influence of the of the magnet and the armatures natural exciting flux of the magnet and the armafrequency will be substantially in 0ppositures natural, frequency will be substantion to the phase of the alternating E. M. F. tially in opposltlon to the phase of the reand a storage battery connected in series sulting E. M. F. and a translating devices with the exciting coilzand thesource of alconnected in series with the exciting coil ternating E. M. F. and the source of alternating E. M. F. In testimony whereof, I have hereunto set 30 2. In an alternat'ng current rectifier, the my hand and afiixed my seal in'the presence combination with a source of alternating of the two subscribing witnesses. E. 1 F., of an electromagnet having an ERNST FASSLER. [L. s.]

BXCllJlIlg coil n circuit with said source, Witnesses:

an armature actuated by said electromagnet .LEO SCHULER, and adapted to establish a short circuit bea JEAN GRUND. 

